Lithium ion battery

ABSTRACT

A multi-core lithium ion battery includes a sealed enclosure and a support member disposed within the sealed enclosure. The sealed enclosure may further include at least two support members housed within individual compartments, separated by shared wall(s). The support member(s) includes a plurality of cavities and a plurality of lithium ion core members which are disposed within the plurality of cavities. The battery may further include a plurality of cavity liners, each of which is positioned between a corresponding one of the lithium ion core members and a surface of a corresponding one of the cavities. The hermetically sealed enclosure may be formed using a clamshell configuration. Structures may be included in proximity to or in contact with the lithium ion core members to control gas/fluid flow therefrom.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part application that claimspriority benefit to a non-provisional patent application entitled“Lithium Ion Battery,” which was filed on Jun. 7, 2017, and assignedSer. No. 15/616,438,and issued on Jan. 16, 2018 as U.S Pat No.9,871,236. The foregoing non-provisional patent application was acontinuation application that claims priority benefit to anon-provisional patent application entitled “Lithium Ion Battery,” whichwas filed on Apr. 10, 2015, and assigned Ser. No. 14/434,848, and issuedon Jun. 20, 2017 as U.S. Pat. No. 9,685,644, which was a nationalapplication filed under Rule 371 based on and claiming priority benefitto PCT/US 2013/064,654 which was filed on Oct. 11, 2013, and whichclaimed priority benefit to a provisional patent application filed onOct. 11, 2012, and assigned Ser. No. 61/795,150. Each of the notedpatent applications is incorporated herein by reference in its entirety.

The present application is also related to the following disclosures:(i) U.S. non-provisional patent application entitled “Low ProfilePressure Disconnect Device for Lithium Ion Batteries,” which was filedon Sep. 28, 2017, and assigned Ser. No. 15/562,792; (ii) PCT applicationentitled “Low Profile Pressure Disconnect Device for Lithium IonBatteries,” which was filed on Dec. 14, 2015, and assigned Serial No.PCT/US16/066663 (republished as WO 2017/106349 on Jun. 22, 2017); (iii)U.S. provisional patent application entitled “Lithium Ion Battery withModular Bus Bar Assemblies,” which was filed on Sep. 22, 2017, andassigned Ser. No. 62/561,927; (iv) U.S. provisional patent applicationentitled “Current Interrupt and Vent Systems for Lithium Ion Batteries,”which was filed on Dec. 14, 2016, and assigned Ser. No. 62/266,813; and(v) U.S. provisional patent application entitled “Current Vent/PressureDisconnect Device System for Lithium Ion Batteries,” which was filed onSep. 15, 2016, and assigned Ser. No. 62/395,050. The entire contents ofthe foregoing patent applications are incorporated herein by reference.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH

This invention was made with government support under DE-AR0000392awarded by the United States Department of Energy. The government hascertain rights in the invention.

FIELD OF DISCLOSURE

This invention relates to lithium ion batteries and more particularly tomulti-core lithium ion batteries having improved safety and reducedmanufacturing costs.

BACKGROUND

The demand for electro-chemical power cells, such as Lithium-ionbatteries, is ever increasing due to the growth of applications such aselectric vehicles and grid storage systems, as well as other multi-cellbattery applications, such as electric bikes, uninterrupted powerbattery systems, and lead acid replacement batteries. It is arequirement for these applications that the energy and power densitiesare high, but just as important, if not more, are the requirements oflow cost manufacturing and increased safety to enable broad commercialadoption. There is further a need to tailor the energy to power ratiosof these batteries to that of the application.

For grid storage and electric vehicles, which are large formatapplications multiple cells connected in series and parallel arrays arerequired. Suppliers of cells are focused either on large cells, hereindefined as more than 10 Ah (Ampere hours) for each single cell, or smallcells, herein defined as less than 10 Ah. Large cells, such as prismaticor polymer cells, which contain stacked or laminated electrodes, aremade by LG Chemical, AESC, ATL and other vendors. Small cells, such as18650 or 26650 cylindrical cells, or prismatic cells such as 183765 or103450 cells and other similar sizes are made by Sanyo, Panasonic,EoneMoli, Boston-Power, Johnson Controls, Saft, BYD, Gold Peak, andothers. These small cells often utilize a jelly roll structure of oblongor cylindrical shape. Some small cells are polymer cells with stackedelectrodes, similar to large cells, but of less capacity.

Existing small and large cell batteries have some significant drawbacks.With regard to small cells, such as 18650 cells, they have thedisadvantage of typically being constrained by a an enclosure or a‘can’, which causes limitations for cycle life and calendar life, due inpart to mechanical stress or electrolyte starvation. As lithium ionbatteries are charged, the electrodes expand. Because of the can, thejelly roll structures of the electrodes are constrained and mechanicalstress occurs in the jelly roll structure, which limits its life cycle.As more and more storage capacity is desired, more active anode andcathode materials are being inserted into a can of a given volume whichresults in further mechanical stresses on the electrode.

Also the ability to increase the amount of electrolyte in small cells islimited and as the lithium intercalates and de-intercalates, theelectrode movement squeezes out the electrolyte from the jelly roll.This causes the electrode to become electrolyte starved, resulting inconcentration gradients of lithium ions during power drain, as well asdry-out of the electrodes, causing side reactions and dry regions thatblock the ion path degrading battery life. To overcome these issues,especially for long life batteries, users have to compromise performanceby lowering the state of charge, limiting the available capacity of thecells, or lowering the charge rate.

On the mechanical side, small cells are difficult and costly to assembleinto large arrays. Complex welding patterns have to be created tominimize the potential for weld failures. Weld failures result inlowered capacity and potential heating at failed weld connections. Themore cells in the array the higher the failure risk and the lowermanufacturing yields. This translates into higher product and warrantycosts. There are also potential safety issues associated not only byfailure issues in welds and internal shorts, but also in packaging ofsmall cells. Proper packaging of small cells is required to avoidcascading thermal runaway as a result of a failure of one cell. Suchpackaging results in increased costs.

For large cells, the disadvantages are primarily around safety, lowvolumetric and gravimetric capacity, and costly manufacturing methods.Large cells having large area electrodes suffer from low manufacturingyields compared to smaller cells. If there is a defect on a large cellelectrode more material is wasted and overall yields are low compared tothe manufacturing of a small cell. Take for instance a 50 Ah cellcompared to a 5 Ah cell. A defect in the 50 Ah cell results in 10×material loss compared to the 5 Ah cell, even if a defect for bothmethods of production only occurs every 50 Ah of produced cells

Another issue for large cells is safety. The energy released in a cellgoing into thermal runaway is proportional to the amount of electrolytethat resides inside the cell and accessible during a thermal runawayscenario. The larger the cell, the more free space is available for theelectrolyte in order to fully saturate the electrode structure. Sincethe amount of electrolyte per Wh for a large cell typically is greaterthan a small cell, the large cell battery in general is a more potentsystem during thermal runaway and therefore less safe. Naturally anythermal runaway will depend on the specific scenario but, in general,the more fuel (electrolyte) the more intense the fire in the case of acatastrophic event. In addition, once a large cell is in thermal runawaymode, the heat produced by the cell can induce a thermal runawayreaction in adjacent cells causing a cascading effect igniting theentire pack with massive destruction to the pack and surroundingequipment and unsafe conditions for users.

When comparing performance parameters of small and large cells relativeto each other, it can be found that small cells in general have highergravimetric (Wh/kg) and volumetric (Wh/L) capacity compared to largecells. It is easier to group multiples of small cells using binningtechniques for capacity and impedance and thereby matching the entiredistribution of a production run in a more efficient way, compared tolarge cells. This results in higher manufacturing yields during batterypack mass production, in addition, it is easier to arrange small cellsin volumetrically efficient arrays that limit cascading runawayreactions of a battery pack, ignited by for instance an internal shortin one cell (one of the most common issue in the field for safetyissues). Further, there is a cost advantage of using small cells asproduction methods are well established at high yield by the industryand failure rates are low. Machinery is readily available and cost hasbeen driven out of the manufacturing system.

On the other hand, the advantage of large cells is the ease of assemblyfor battery pack OEMs, which can experience a more robust large formatstructure which often has room for common electromechanical connectorsthat are easier to use and the apparent fewer cells that enableseffective pack manufacturing without having to address the multipleissues and know-how that is required to assemble an array of smallcells.

In order to take advantage of the benefits of using small cells tocreate batteries of a larger size and higher power/energy capability,but with better safety and lower manufacturing costs, as compared tolarge cells, assemblies of small cells in a multi-core (MC) cellstructure have been developed.

One such MC cell structure, developed by BYD Company Ltd., uses an arrayof MC's integrated into one container made of metal (Aluminum, copperalloy or nickel chromium). This array is described in the followingdocuments: EP 1952475 AO; WO2007/053990; US2009/0142658 A1; CN 1964126A.The BYD structure has only metallic material surrounding the MCs andtherefore has the disadvantage during mechanical impact of having sharpobjects penetrate into a core and cause a localized short. Since all thecores are in a common container (not in individual cans) whereelectrolyte is shared among cores, propagation of any individualfailure, from manufacturing defects or external abuse, to the othercores and destruction of the MC structure is likely. Such a cell isunsafe.

Methods for preventing thermal runaway in assemblies of multipleelectrochemical cells have been described in US2012/0003508 A1. In theMC structure described in this patent application, individual cells areconnected in parallel or series, each cell having a jelly roll structurecontained within its own can. These individual cells are then insertedinto a container which is filled with rigid foam, including fireretardant additives. These safety measures are costly to produce andlimit energy density, partly due to the excessive costs of themitigating materials.

Another MC structure is described in patent applications US2010/0190081A1 and WO2007/145441 A1, which discloses the use of two or morestacked-type secondary batteries with a plurality of cells that providetwo or more voltages by a single battery. In this arrangement singlecells are connected in series within an enclosure and use of aseparator. The serial elements only create a cell of higher voltage, butdo not solve any safety or cost issues compared to a regularlystacked-type single voltage cell.

These MC type batteries provide certain advantages over large cellbatteries; however, they still have certain shortcomings in safety andcost.

SUMMARY

The present disclosure provides a novel type MC lithium ion batterystructure, having reduced production costs and improved safety whileproviding the benefits of a larger size battery, such as ease ofassembly of arrays of such batteries and an ability to tailor power toenergy ratios.

A multi-core lithium ion battery is described having a sealed enclosurewith a support member disposed within the sealed enclosure. The supportmember including a plurality of cavities and a plurality of lithium ioncore members, disposed within a corresponding one of the plurality ofcavities. There are a plurality of cavity liners, each positionedbetween a corresponding one of the lithium ion core members and asurface of a corresponding one of the cavities. The support memberincludes a kinetic energy absorbing material and the kinetic energyabsorbing material is formed of one of aluminum foam, ceramic, andplastic. The cavity liners are formed of a plastic material and theplurality of cavity liners are formed as part of a monolithic linermember. There is further included an electrolyte contained within eachof the cores and the electrolyte includes at least one of a flameretardant, a gas generating agent, and a redox shuttle. Each lithium ioncore member includes an anode, a cathode and a separator disposedbetween each anode and cathode. There is further included an electricalconnector within said enclosure electrically connecting said coremembers to an electrical terminal external to the sealed enclosure. Theelectrical connector includes two bus bars, the first bus barinterconnecting the anodes of said core members to a negative terminalmember of the terminal external to the enclosure, the second bus barinterconnecting the cathodes of said core members to a positive terminalmember of the terminal external to the enclosure.

In another aspect of the disclosure, a compartmentalized enclosure for alithium ion battery is provided that includes at least two supportmembers, that house lithium ion core members, in parallel and/or series.Exemplary lithium ion core members for inclusion in the disclosedsupport members take the form of jelly rolls with a cylindrical (orsubstantially cylindrical) shape. The compartmentalized enclosurefurther includes at least one shared wall that functions to separatefirst and second compartments from each other. The first/secondcompartments may define a shared atmosphere across the two compartments,or the shared wall may function to define distinct/individual atmospherein the respective compartments, i.e., the shared wall functions todefine a first hermetically sealed region in the first compartment, anda second hermetically sealed region in the second compartment.

In implementations of the present disclosure wherein the shared wall ofthe compartmentalized enclosure defines a shared atmosphere acrossfirst/second compartments, the disclosed compartmentalized enclosure mayadvantageously include at least one pressure disconnect device/featurein communication with the shared atmosphere. Thus, in exemplaryembodiments, a single pressure disconnect device/feature may be providedthat is effective in providing pressure disconnect functionality forboth first and second compartments.

In implementation of the present disclosure wherein the shared wall ofthe compartmentalized enclosure defines distinct first/secondcompartments, multiple pressure disconnect devices/feature may beadvantageously provided, i.e., a first pressure disconnectdevice/feature for the first compartment and a second pressuredisconnect device/feature for the second compartment.

In another aspect of the disclosure, the core members are connected inparallel or they are connected in series. Alternatively, a first set ofcore members are connected in parallel and a second set of core membersare connected in parallel, and the first set of core members isconnected in series with the second set of core members. The supportmember is in the form of a honeycomb structure. The kinetic energyabsorbing material includes compressible media. The enclosure includes awall having a compressible element which when compressed due to a forceimpacting the wall creates an electrical short circuit of the lithiumion battery. The cavities in the support member and their correspondingcore members are one of cylindrical, oblong, and prismatic in shape. Theat least one of the cavities and its corresponding core member havedifferent shapes than the other cavities and their corresponding coremembers.

In another aspect of the disclosure, the at least one of the coremembers has high power characteristics and at least one of the coremembers has high energy characteristics. The anodes of the core membersare formed of the same material and the cathodes of the core members areformed of the same material. Each separator member includes a ceramiccoating and each anode and each cathode includes a ceramic coating. Atleast one of the core members includes one of an anode and cathode of adifferent thickness than the thickness of the anodes and cathodes of theother core members. At least one cathode includes at least two out ofthe Compound A through M group of materials. Each cathode includes asurface modifier. Each anode includes Li metal or one of carbon orgraphite. Each anode includes Si. Each core member includes a rolledanode, cathode and separator structure or each core member includes astacked anode, cathode and separator structure.

In another aspect of this disclosure, the core members havesubstantially the same electrical capacity. At least one of the coremembers has a different electrical capacity than the other core members.At least one of the core members is optimized for power storage and atleast one of the core members is optimized for energy storage. There isfurther included a tab for electrically connecting each anode to thefirst bus bar and a tab for electrically connecting each cathode to thesecond bus bar, wherein each tab includes a means for interrupting theflow of electrical current through each said tab when a predeterminedcurrent has been exceeded. The first bus bar includes a fuse element,proximate each point of interconnection between the anodes to the firstbus bar and the second bus bar includes a fuse element proximate eachpoint of interconnection between the cathodes to the second bus bar, forinterrupting the flow of electrical current through said fuse elementswhen a predetermined current has been exceeded. There is furtherincluded a protective sleeve surrounding each of the core members andeach protective sleeve is disposed outside of the cavity containing itscorresponding core member.

In yet another aspect of the disclosure, there are include sensing wireselectrically interconnected with said core members configured to enableelectrical monitoring and balancing of the core members. The sealedenclosure includes a fire retardant member and the fire retardant memberincludes a fire retardant mesh material affixed to the exterior of theenclosure.

In another embodiment, there is described a multi-core lithium ionbattery comprising a sealed enclosure. A support member is disposedwithin the sealed enclosure, the support member including a plurality ofcavities, wherein the support member includes a kinetic energy absorbingmaterial. There are a plurality of lithium ion core members, disposedwithin a corresponding one of the plurality of cavities. There isfurther included a plurality of cavity liners, each positioned between acorresponding one of the lithium ion core members and a surface of acorresponding one of the cavities. The cavity liners are formed of aplastic material and the plurality of cavity liners are formed as partof a monolithic liner member. The kinetic energy absorbing material isformed of one of aluminum foam, ceramic, and plastic.

In another aspect of the disclosure, there is an electrolyte containedwithin each of the cores and the electrolyte includes at least one of aflame retardant, a gas generating agent, and a redox shuttle. Eachlithium ion core member includes an anode, a cathode and separatordisposed between each anode and cathode. There is further included anelectrical connector within said enclosure electrically connecting saidcore members to an electrical terminal external to the sealed enclosure.The electrical connector includes two bus bars, the first bus barinterconnecting the anodes of said core members to a negative terminalmember of the terminal external to the enclosure, the second bus barinterconnecting the cathodes of said core members to a positive terminalmember of the terminal external to the enclosure. The core members areconnected in parallel. The core members are connected in series. Thelithium ion battery may include a first set of core members that areconnected in parallel and a second set of core members that areconnected in parallel, and the first set of core members may beconnected in series with the second set of core members.

In another aspect, the support member is in the form of a honeycombstructure. The kinetic energy absorbing material includes compressiblemedia. The lithium enclosure includes a wall having a compressibleelement which when compressed due to a force impacting the wall createsan electrical short circuit of the lithium ion battery. The cavities inthe support member and their corresponding core members are one ofcylindrical, oblong, and prismatic in shape. At least one of thecavities and its corresponding core member have different shapes thanthe other cavities and their corresponding core members. At least one ofthe core members has high power characteristics and at least one of thecore members has high energy characteristics. The anodes of the coremembers are formed of the same material and the cathodes of the coremembers are formed of the same material. Each separator member includesa ceramic coating. Each anode and each cathode includes a ceramiccoating. At least one of the core members includes one of an anode andcathode of a different thickness than the thickness of the anodes andcathodes of the other core members.

In yet another aspect, at least one cathode includes at least two out ofthe Compound A through M group of materials. Each cathode includes asurface modifier. Each anode includes Li metal, carbon, graphite or Si.Each core member includes a rolled anode, cathode and separatorstructure. Each core member includes a stacked anode, cathode andseparator structure. The core members have substantially the sameelectrical capacity. Wherein at least one of the core members has adifferent electrical capacity than the other core members. At least oneof the core members is optimized for power storage and at least one ofthe core members is optimized for energy storage.

In another aspect of the disclosure, there is further included a tab forelectrically connecting each anode to the first bus bar and a tab forelectrically connecting each cathode to the second bus bar, wherein eachtab includes a means for interrupting the flow of electrical currentthrough each said tab when a predetermined current has been exceeded.The first bus bar includes a fuse element, proximate each point ofinterconnection between the anodes to the first bus bar and a fuseelement, proximate each point of interconnection between the cathodes tothe second bus bar, for interrupting the flow of electrical currentthrough said fuse elements when a predetermined current has beenexceeded. There is further included a protective sleeve surrounding eachof the core members and each protective sleeve is disposed outside ofthe cavity containing its corresponding core member.

In another embodiment of the disclosure, there are sensing wireselectrically interconnected with said core members configured to enableelectrical monitoring and balancing of the core members. The sealedenclosure includes a fire retardant member and the fire retardant memberincludes a fire retardant mesh material affixed to the exterior of theenclosure.

In another embodiment, a multi-core lithium ion battery is describedwhich includes a sealed enclosure, with a lithium ion cell region and ashared atmosphere region in the interior of the enclosure. There is asupport member disposed within the lithium ion cell region of the sealedenclosure and the support member includes a plurality of cavities, eachcavity having an end open to the shared atmosphere region. There are aplurality of lithium ion core members, each having an anode and acathode, disposed within a corresponding one of the plurality ofcavities, wherein said anode and said cathode are exposed to the sharedatmosphere region by way of the open end of the cavity and said anodeand said cathode are substantially surrounded by said cavity along theirlengths. The support member includes a kinetic energy absorbingmaterial. The kinetic energy absorbing material is formed of one ofaluminum foam, ceramic and plastic.

In another aspect, there are a plurality of cavity liners, eachpositioned between a corresponding one of the lithium ion core membersand a surface of a corresponding one of the cavities and the cavityliners are formed of a plastic material. The pluralities of cavityliners are formed as part of a monolithic liner member. There is anelectrolyte contained within each of the cores and the electrolyteincludes at least one of a flame retardant, a gas generating agent, anda redox shuttle. Each lithium ion core member includes an anode, acathode and separator disposed between each anode and cathode. There isan electrical connector within said enclosure electrically connectingsaid core members to an electrical terminal external to the sealedenclosure. The electrical connector includes two bus bars, the first busbar interconnecting the anodes of said core members to a negativeterminal member of the terminal external to the enclosure, the secondbus bar interconnecting the cathodes of said core members to a positiveterminal member of the terminal external to the enclosure.

In yet another aspect, the core members are connected in parallel or thecore members are connected in series. Alternatively, a first set of coremembers are connected in parallel and a second set of core members areconnected in parallel, and the first set of core members is connected inseries with the second set of core members.

In another embodiment, a lithium ion battery is described and includes asealed enclosure and at least one lithium ion core member disposedwithin the sealed enclosure. The lithium ion core member having an anodeand a cathode, wherein the cathode includes at least two compoundsselected from the group of Compounds A through M. There is only onelithium ion core member. The sealed enclosure is a polymer bag or thesealed enclosure is metal canister. Each cathode includes at least twocompounds selected from group of compounds B, C, D, E, F, G L, and M andfurther including a surface modifier. Each cathode includes at least twocompounds selected from group of Compounds B, D, F, G, and L. Thebattery is charged to a voltage higher than 4.2V. Each anode includesone of carbon and graphite. Each anode includes Si.

In yet another embodiment a lithium ion battery is described having asealed enclosure and at least one lithium ion core member disposedwithin the sealed enclosure. The lithium ion core member having an anodeand a cathode. An electrical connector within said enclosureelectrically connecting said at least one core member to an electricalterminal external to the sealed enclosure; wherein the electricalconnector includes a means for interrupting the flow of electricalcurrent through said electrical connector when a predetermined currenthas been exceeded. The electrical connector includes two bus bars, thefirst bus bar interconnecting the anodes of said core members to anegative terminal member of the terminal external to the enclosure, thesecond bus bar interconnecting the cathodes of said core members to apositive terminal member of the terminal external to the enclosure. Theelectrical connector further includes a tab for electrically connectingeach anode to the first bus bar tab for electrically connecting eachcathode to the second bus bar, wherein each tab includes a means forinterrupting the flow of electrical current through each said tab when apredetermined current has been exceeded. The electrical connectorwherein first bus bar includes a fuse element, proximate each point ofinterconnection between the anodes to the first bus bar and the secondbus bar includes a fuse element, proximate each point of interconnectionbetween the cathodes to the second bus bar, for interrupting the flow ofelectrical current through said fuse elements when a predeterminedcurrent has been exceeded.

In another aspect, an enclosure is fabricated using a clamshellconfiguration wherein symmetrically identical side wall components areattached together along a pair of seams to define the completeenclosure. The clamshell components may be fabricated using plastic orceramic materials, but may also be made of metal. The clamshellconfiguration(s) may provide a cost-savings by substantially reducingmanufacturing/assembly operations.

In yet another aspect, one or more blanket-like structures may beprovided within the disclosed enclosure. The blanket-like structure(s)are generally configured and dimensioned so as to be positionable inproximity to the electrochemical elements, e.g., atop an open jellyroll, such that any gas/fluid flow into or from the electrochemicalelement(s) encounters the blanket-like structure. Thus, the blanket-likestructure may advantageously function to substantially limit thequantity of hot particulate residue, e.g., liquid electrolyte andelectrolyte gas, that may be emitted from the electrochemical unit fromundesirably interacting with adjacent electrochemical units/jelly rolls.The blanket-like structure(s) may feature flow characteristics thatpromote axial gas flow relative to the blanket-like structure, but thatsubstantially reduces lateral (e.g., side-to-side) flow therewithin.Therefore, according to exemplary embodiments, gas and/or other fluidsthat are emitted by an electrochemical element/jelly roll ispreferentially directed in a substantially axial manner through theblanket-like structure to an atmospheric region defined thereabove. Tothe extent the pressure within the atmospheric region exceeds anapplicable pressure threshold, a vent mechanism associated with thepresent disclosure may be activated, whereby the gas is vented from theenclosure to the external environment.

Additional features, functions and benefits of the present disclosurewill be apparent from the detailed description which follows,particularly when read in conjunction with the appended figures.

BRIEF DESCRIPTION OF THE FIGURES

The disclosure will be better understood on reading the descriptionwhich follows, given solely by way of non-limiting example and made withreference to the drawings in which:

FIG. 1A is an exploded perspective view of the multicore, lithium ionbattery according to this disclosure;

FIG. 1B is a cross-sectional view of the multicore, lithium ion batteryaccording to this disclosure;

FIG. 1C is a stress-strain plot of an exemplary energy absorbingmaterial of the support member according to this disclosure;

FIG. 1D is a cross-sectional view of another embodiment of multicore,lithium ion battery according to this disclosure;

FIG. 2 is a top down view of a plurality of support memberconfigurations according to this disclosure;

FIG. 3 is a perspective view of another embodiment of the multicore,lithium ion battery according to this disclosure;

FIG. 4 is a perspective view of another embodiment of support memberhaving mixed oblong and cylindrical cavities according to thisdisclosure;

FIG. 5 is a perspective view of prismatic wound and stacked core membersaccording to this disclosure;

FIG. 6A depicts a parallel/series connected MC lithium ion batteryaccording to this disclosure;

FIG. 6B is a perspective view of a parallel/series connected MC lithiumion battery according to this disclosure;

FIG. 7 is a top down view of a modular enclosure according to thisdisclosure;

FIG. 8 is an exploded perspective view of a MC lithium ion batteryaccording to this disclosure;

FIG. 9A is a cross-sectional view of an egg-box shaped wall of theenclosure according to this disclosure;

FIG. 9B is a cross-sectional view of an egg-box shaped wall of theenclosure according to this disclosure during a mechanical impact on thewall; and

FIG. 10 is a perspective view of an exemplary side wall componentaccording to an exemplary embodiment of the present disclosure.

DETAILED DESCRIPTION

Multi-Core Array

In FIGS. 1A and 1B there is shown a multi-core (MC) array 100 of lithiumion core members 102 a-j, having a jelly roll cores structure and acylindrical shape. Various shapes and size ion core members may be usedin connection with this disclosure and certain shapes and sizes aredescribed below. There is a set of electrically conductive tabs 104connected to the cathodes of each of the core members 102 a-j and a setof electrically conductive tabs 106 connected to the anodes of each ofthe core members 102 a-j. Tabs 104 are also connected to cathode bus bar108 and tabs 106 are connected to anode bus bar 110. The cathode tabs104 and the anode tabs 106 are welded to the bus bars 108, 110 usingspot welding or laser welding techniques. The bus bars 108, 110 areinterconnected to positive terminal 112 and negative terminal 114,respectively, on the exterior of the MC enclosure 116. In thisconfiguration, all of the ion core members 102 a-j are connected inparallel, but they may be connected in series or in other configurationsas will be apparent to those skilled in the art.

MC enclosure 116, FIG. 1B, is hermetically sealed. The support structure120, which can be a part of the enclosure 116 or a separate part isconstructed so that ion core members can be housed with adequateseparation, so that limited expansion can take place during charge anddischarge reactions thereby preventing mechanical interaction of theindividual ion core members. Preferably enclosure 116 is made of plasticor ceramic materials, but can also be made of metal. If a metal is used,exposed steel is not preferred, and any steel container would need to becoated with an inert metal such as nickel. Preferred metals areAluminum, Nickel or other inert metal to the chemicals used. Many typesof plastic and ceramic as long as they are inert to the chemical andelectrochemical environment. Examples of plastics and ceramics arepolypropylene, polyethylene, alumina, zirconia. Enclosure 116 caninclude a fire retardant mesh affixed to the exterior of the enclosurefor the purpose of preventing fire from reaching the interior of theenclosure.

Within enclosure 116, in lithium ion core region 118, is an electricallyinsulated support member 120 which can be made of ceramic, plastic, suchas polypropylene, polyethylene, or other materials, such as aluminumfoam. Support member 120 must be sufficiently deformable/compressible soas to protect the core members from damage when an impact occurs. Inaddition it is desired that the thermal conductivity be tailored to theapplication by means of dispersing heat during charge and discharge ofthe battery, creating a uniform temperature distribution, and by meansof diverging heat during a catastrophic failure, such as an internalshort causing thermal runaway of one core member. Proper heat dispersingproperties would limit the chance of cascading runaway between cores.The support member can also be absorptive to electrolyte, which could beconstrained in the support member, should it be expelled during abuse ofthe core member.

A deformable and kinetic energy absorbing support member 120 isparticularly desirable, as it distributes impact loads over larger areasreducing the amount of local deformation at each core member 102 a-j,thereby reducing the likelihood of an electric short circuit. Examplesof kinetic energy absorbing materials are foams, such as aluminum foam,plastic foams, porous ceramic structures, honeycomb structures, or otheropen structures, fiber filled resins, and phenolic materials. An exampleof fiber fillers for plastic and resin materials could be glass fiber orcarbon fibers. Examples of aluminum containing energy absorbers arealuminum foam, having open or closed pores, aluminum honeycombstructures, and engineered material such as the Altucore™ and CrashLite™materials. As the support member collapses during impact, crash or othermechanical abuse, it is important that the cores, as much as possible,are protected from penetration as to avoid internal mechanically inducedshorts. This creates a safer structure.

Energy absorbers are a class of materials that generally absorb kineticmechanical energy by compressing or deflecting at a relatively constantstress over an extended distance, and not rebounding. Springs perform asomewhat similar function, but they rebound, hence they are energystorage devices, not energy absorbers. Once an applied stress exceedsthe “crush plateau”, see 150 of FIG. 1C, of the kinetic energy absorbermaterial, the energy absorber will begin to compress at a fairlyconstant stress out to about 50-70% of strain of the material. Thisextended section of the stress/strain curve defines the behavior of anideal energy absorber. In this zone, the area under the curve representsthe product of stress x strain, or “work”. In an actual block of energyabsorber material of a finite size, such as support member 120, thiswould be represented as:Force×DisplacementRecognizing thatForce (pounds)×Displacement (feet)=Work (foot·pounds)andWork (foot·pounds)=kinetic energy (foot·pounds)

The work that would be done to compress support member 120 is equivalentto the kinetic energy of a mass that might impact support member 120.When designed with appropriate thickness and compression strength, aswill be apparent to one skilled in the art, support member 120 may bemade of kinetic energy absorbing material could absorb all of thekinetic energy of an impact on the battery, for example in a crash of anelectric vehicle. Most importantly, the cargo in the support members120, i.e. the lithium ion core members 102 a-j, would never see a forcehigher than the crush strength of the material (defined below). Thus, byabsorbing the energy of the impacting mass over a controlled distancewith a constant force, the protected structure, i.e., the lithium ioncore members 102 a-j, would not have to endure a concentratedhigh-energy/high force impact that would occur if the mass impacted thestructure directly, with potentially catastrophic results.

When a load is applied to a structure made of an energy absorbingmaterial, it will initially yield elastically in accord with the Young'smodulus equation. However, at approximately 4-6% of strain, 152 of FIG.1C, in this particular example of Al foam, depending on the structuresize it will begin to buckle and collapse continuously at a relativelyconstant stress. Depending upon the initial relative density of thematerial, this constant collapse will proceed to approximately 50-70% ofstrain, 154 of FIG. 1C, for this Al foam material. At that point, thestress/strain curve will begin to rise as the energy absorbing materialenters the “densification” phase. The point in the stress/strain curvewhere the material transitions from the elastic to plastic deformationphase defines the “crush strength” of the material.

The long, relatively flat section of the curve between the 4-6%transition and 50-70% of strain (covering approximately 45-65% of thepossible strain values of the material), called the “crush plateau. Thisunique characteristic of kinetic energy absorbing materials makes themvery useful to absorb the kinetic energy of an impacting mass whileprotecting the cargo being carried.

To further protect the core member, a cylindrical material made ofmetal, ceramic or plastic may be added as a sleeve 121, FIG. 1A, aroundthe core structure. This sleeve can either be added directly surroundingthe individual cores, on the outside of the liner material, or beapplied the inside of the cavities structures in the support member.This prevents sharp objects from penetrating the cores. Although onlyone sleeve is shown in the figure it will be readily understood thatsleeves would be included for each core member.

Support member 120 could alternatively be designed with open regions160, as shown in FIG. 1D, which contain filling materials 162. Examplesof filling materials are irregularly or regularly shaped media, whichcan be hollow or dense. Examples of hollow media are metal, ceramic orplastic spheres, which can be made compressible at various pressureforces and with the purpose of functioning as an energy absorber forcrash protection. Specific examples are aluminum hollow spheres, ceramicgrinding media of alumina or zirconia, and polymer hollow spheres.

Support member 120 may also is optimized to transfer heat rapidlythroughout the support member and distribute it evenly throughout thebattery or limit heat exposure between cores, should one core experiencethermal runaway during abuse. Besides greater safety, this will increasebattery life by limiting maximum operating temperatures and enable thebattery to have no, or passive, thermal management. Most importantly,the thermal characteristics of support member 120 help to preventfailure propagation from a failed core member to other core members dueto the optimized heat transfer properties of the material and theability to disrupt flame propagation. Since the material is alsoabsorptive, it can absorb leaking electrolyte into the material whichcan help reduce the severity of a catastrophic failure.

Support member 120 increases overall safety of the MC battery by a)allowing the distribution of the ion core members 102 a-j to optimizethe battery for both safety and high energy density, b) arresting rapidthermal propagation ion core members 102 a-j, while simultaneouslyallowing cooling, c) providing a protective crash and impact absorbingstructure for ion core members 102 a-j and the reactive chemicals, andd) use of a widely recognized fire proof material through flame arrest.

Cylindrical cavities 122 are formed in support member 120 for receivingthe lithium ion core members 102 a-i, one core per cavity. In thisconfiguration, the cylindrical cavities 122 have openings 126 with adiameter that is slightly larger than those of the lithium ion coremembers 102. Openings 126 face and are exposed to shared atmosphereregion 128 within enclosure 116. The walls of the cylindrical cavities122 are advantageously fabricated such that electrolyte communicationbetween adjacent cavities is prevented. Thus, the walls of the cavities122 function to enclose the electrochemical units/jelly rolls positionedtherewithin and prevent fluid passage from any individual cavity to anyadjacent cavity.

Without having individual smaller enclosures (such as a can or polymerbag that hermetically provides a seal between the active core members),the anodes/cathodes of the core members are also directly exposed to theshared environment region 128. Not only does the elimination of thecanned core members reduce manufacturing costs, it also increasessafety. In the event of a failure of a core member and a resulting fire,the gasses expelled are able to occupy the shared environment region128, which provides significantly more volume than would be available ina typical individually ‘canned’ core member. With the canned core memberpressure build up, an explosion is more likely than with the presentdisclosure, which provides a greater volume for the gases to occupy andtherefore reduced pressure build up. In addition, a can typicallyruptures at much higher pressures than the structure of the disclosure,resulting in a milder failure mode with the present disclosure.

Within each cavity 122 is placed a thin cavity liner 124, which ispositioned between support member 120 and lithium ion core members 102a-i. Typically, all cavity liners (in this case 10 corresponding to thenumber of cavities) are formed as part of a monolithic cavity linermember 124′. The liner is preferably made out of polypropylene,polyethylene, or any other plastic that is chemically inert toelectrolyte. The liner may also be made of a ceramic or metal material,although these are at higher cost and non-preferred. However, in thecase where the support member is electrically conductive, the liner mustbe electrically insulating so as to electrically isolate the coremembers from the support member. The cavity liners are important formultiple reasons. First, they are moisture and electrolyte impermeable.Secondly, they may contain flame retarding agents, which can quench afire and thirdly, they allow a readily sealable plastic material tocontain the electrolyte within a hermetic seal.

During manufacturing, cavities 122 can be simultaneously filled withelectrolyte and then simultaneously formed and graded for capacityduring the continued manufacturing process. The forming process consistof charging the cell to a constant voltage, typically 4.2V and thenletting the cell rest at this potential for 12-48 hours. The capacitygrading takes place during a charge/discharge process, where the cell isfully discharged to a lower voltage, such as 2.5V, then charged tohighest voltage, typically in a range of 4.2-4.5V, and subsequentlydischarged again, upon which the capacity is recorded. Multiplecharge/discharge cycles may be needed to obtain an accurate capacitygrading, due to inefficiencies in the charge/discharge process.

The cavity liner enables a precise and consistent amount of electrolyteto be introduced to each core member, due to its snug fit with the core.One way to accomplish the filling is with through holes in enclosure 116which can then be filled and sealed after the electrolyte has beenintroduced to the cavities and processed. A jelly roll type core memberhaving about 3 Ah capacity will need about 4-8 g of electrolyte,depending on density and surrounding porous material. Electrolytefilling is done so that entire jelly roll is equally wetted throughoutthe roll with no dry areas allowed. It is preferred that each coremember has the equivalent amount of electrolyte from core to core, witha variation within 0.5 g, and even more preferred within 0.1 g and yeteven more preferred within 0.05 g. The variation adjusts with the totalamount electrolyte and is typically less than 5% or even more preferred<1% of the total amount of electrolyte per core. Placing the assembly ina vacuum helps with this filling process and is crucial for full andequal wetting of the electrodes.

The size, spacing, shape and number of cavities 122 in support member120 can be adjusted and optimized to achieve the desired operatingcharacteristics for the battery while still achieving the safetyfeatures described above, such as mitigating failure propagationbetween/among core members 102.

As shown in FIG. 2, support members 220 a-h may have different numbersof cavities, preferably ranging from 7 to 11, and differentconfigurations, including support members having different size cavitiesas in the case of support members 220 d and 220 h. The number ofcavities is always more than 2 and is not particularly limited on theupper end, other than by geometry of the support member and jelly rollsize. A practical number of cavities are typically between 2 and 30. Thecavities can be uniformly distributed, as in support member 220 f, orthey can be staggered, as in the case of support member 220 g. Alsoshown in FIG. 2 are the cavity diameters and diameter of the core memberthat can be inserted into the cavities for each of the support members220 a-h depicted, in addition, the capacity of in Ampere hours (Ah) foreach configuration is shown.

Different shaped cavities and core members can be used as well. As shownin FIG. 3, support member 320 includes cavities 322 having an oblongshape for receiving like shaped core members 302. In FIG. 4, supportmember 420 has a mixture of oblong cavities 422 and cylindrical cavities402 for receiving like shaped core members (not shown).

In an exemplary embodiment, when the MC battery has only core membersarranged in parallel, the core members may contain one or more coremembers that are optimized for power and one or more core members thatare optimized for energy. In another special case, the MC battery mayhave some core members with anode or cathode using certain materials andother core members utilizing anodes and cathodes using differentmaterials. In yet another special case, the anode or cathode, may havedifferent thickness electrodes. Any combination of having varyingelectrode thickness, cathode or anode active material, or electrodeformulation may be combined in a parallel string, with the objective oftailoring the energy to power ratio of the battery. Some core membersmay be configured to withstand rapid power pulses, while other coremembers may be optimized for high energy storage thus providing abattery that can handle high power pulses, while having high energycontent. It is important however that the core members have chemistrythat is matched electrochemically, so as to provide chemical stabilityin the voltage window for the chemistry chosen.

For instance, a LiCoO₂ cathode can be matched with aLiNi_(0.8)Co_(0.15)Al_(0.05)O₂ cathode, as long as an upper potential of4.2V is used and a lower potential of about 2V to 2.5V, however, aspotential goes above 4.2V, to for instance 4.3V, for instance amagnesium doped LiCoO₂ material should not be matched with an NCAmaterial, as the NCA material degrades at the higher voltages. However,in the latter example, the two materials can be mixed as long as theupper potential is limited to 4.2V. It is an objective of the disclosureto use blended cathode materials in the correct voltage range and theinventor has found certain combinations that are particularly useful forhigh energy or high power, elaborated on later in the description.

The power and energy optimization can take place by either adjusting theformulation of the electrode, such as using higher degree of conductiveadditive for increased electrical conductivity, or by using differentthickness electrodes. Additionally the energy cores can have one set ofactive materials (cathode and anode) and the power cores another type ofmaterials. When using this method it is preferred that the materialshave matched voltage range, such as 2.5-4.2V or in case of high voltagecombinations 2.5V-4.5V, so as to avoid decomposition. Upper voltage ischaracterized as above 4.2V and is typically below 5V per isolated coremember in a Li-ion multi-core battery.

Prismatic Core Member

In FIG. 5, an exemplary shape of core member 502 a, suitable for thisdisclosure is shown. This is a jelly roll structure, but with aprismatic shape rather than cylindrical or oblong as previouslydescribed. The core member includes anode 530 a, cathode 532 a andelectrically insulating separator 534 a. Although not depicted in theprevious figures each core member includes a separator between theanodes and the cathodes. Core member 502 b is also prismatic in shape,however, a stacked construction is used, includes anode 530 b, cathode532 b and separator 534 b.

Serial Connection

Thus far the core members have been shown electrically connected in aparallel, however, they may be connected in series or in a combinationof parallel and series connections. As shown in FIG. 6, there is supportmember 620 (made of aluminum foam or polymer foam) together withinserted jelly rolls core members 602. For clarity, the tabs to the coremembers connecting to the bus bars are not shown, but present. Negativebattery terminal connector 640 is electrically connected to the lowervoltage bus bar 642. Positive battery terminal connector 644 iselectrically connected to the high voltage bus bar 646. Adjacent blockbus bars 648 and 650 connect each the core members in their respectiverows in parallel. Each bus bar 642, 644, 648 and 650 has a complementarybus bar on the opposite side of the core member, which is not shown.Every parallel bus bar is individually connected in series through threeconnecting bars, 652, allowing a serial electrical path. Sensing cables654 a-654 e are positioned on each electrical unique point, allowingdetection of voltage levels across each of the parallel linked jellyroll voltage points in a serial system. These wires can also be used forproviding balancing current to keep core members at the same state ofcharge during charge and discharge and are connected to a feed throughcontact 656. Those skilled in the art of cell balancing systems willrealize the purpose of such connections within a unit of the disclosurehaving serially connected cores.

FIG. 6B shows an enclosure 616 that houses the support member 320.Enclosure 616 consist of a plastic lid 658 and a box 660 that arehermetically sealed through ultrasonic welding. At the end of enclosure616 opposite the side of lid 658 is the feed through sensing contact656. Extending from lid 658 are negative battery terminal connector 640and positive battery terminal connector 644. It can be understood thatvarious arrangements as to the position of the connectors sensingcontact can be achieved by those skilled in the art and also thatdifferent serial or parallel arrangement cells can be used for thepurpose of the disclosure.

In the case of a metal lid it is closed with welding methods, such aslaser welding, and in the case of plastics, adhesives (glues) can beused, or thermal or ultrasonic weld methods can be used, or anycombination thereof. This provides for a properly sealed MC battery.Jelly rolls are connected in parallel or series inside the enclosure.

All feedthroughs, sensing, power, pressure, etc., needs to behermetically sealed. The hermetical seals should withstand internalpressure of in excess or equal to about 1 atm and also vacuum,preferably more than 1.2 atm. A vent can also be housed on thecontainer, set at a lower internal pressure than the seal allows.

Another way of providing balancing and sensing ability is to haveindividual connectors that provide an external lead from each of thepositive and negative terminals of individual core members allowingconnectors external to the container to connect with each of theindividual core members. The balancing circuit detects imbalance involtage or state-of-charge of the serial cells and would provide meansof passive of active balancing known to those skilled in the art. Theconnecting leads are separate from the terminals providing means ofleading current from the cells for the purpose of providing power fromthe battery and typically only used when cells are connected in serieswithin one container. The sensing leads can optionally be fused outsidethe container, for avoidance of running power currents through theindividual jelly rolls through the sensing circuit.

Shared Wall Compartmentalization

In an exemplary embodiment, as shown in FIG. 7, module 700 includes acompartmentalized enclosure 702 that further includes a plurality ofsupport members 704—e.g., a distinct support member 704 in eachcompartmentalized region 705. Support members 704, as described above,house lithium ion core members 102, e.g., open jelly rolls with asubstantially cylindrical shape. In the exemplary embodiment of FIG. 7,the lithium ion core members are arrayed in a series of rows that arestaggered relative to adjacent rows to increase the density ofelectrochemical unit deployment. Various shapes and size lithium ioncore members may be used in connection with this disclosure and certainshapes and sizes are described throughout this disclosure. Of note, theteachings described above are incorporated into this subheading, unlessotherwise stated. In this configuration, all lithium ion core members102 are connected in parallel, but they may be connected in series or inother configurations as will be apparent to those skilled in the art.

In one embodiment, included within enclosure 702 is a set ofelectrically conductive tabs (not shown) connected to the cathodes ofeach core member 102 and a set of electrically conductive tabs (notshown) connected to the anodes of each core member 102. Tabs (not shown)are also connected to cathode bus bar (not shown) and tabs (not shown)are connected to anode bus bar (not shown). The cathode tabs (not shown)and anode tabs (not shown) are welded to bus bars (not shown) using spotwelding or laser welding techniques. Bus bars (not shown) areinterconnected to positive terminal (not shown) and negative terminal(not shown), respectively, on the exterior of module enclosure 702.

In another embodiment, included within enclosure 702 is a first bus bar(not shown) interconnecting the anodes of the core members to a positiveterminal member of the terminal external to the enclosure, and thesecond bus bar (not shown) interconnecting the cathodes of the coremembers to a negative terminal member of the terminal external to theenclosure 702. A bus bar may be used for pressure disconnectconfigurations, described in more detail below. The first and second busbars may be fabricated from any conductive material, particularly,aluminum and/or copper.

Support member 704, which can fabricated as part of enclosure 702 or asa separate part, defines cavities that are configured and dimensioned sothat lithium ion core members 102 positioned therewithin have sufficientspace such that limited expansion can take place during charge anddischarge reactions, thereby preventing mechanical interaction of theindividual lithium ion core members during typical charge/dischargeoperations. Preferably, support members 704 are fabricated from aplastic or ceramic material, but fabrication (in whole or in part) froma metal is also contemplated. Enclosure 702 may also be fabricated fromvarious materials, e.g., plastic, ceramic, metal and combinationsthereof. If a metal is used, exposed steel is not preferred, and it isgenerally advantageous to coat a metallic (e.g., steel) enclosure 702with an inert metal such as nickel. Preferred metals are aluminum,nickel or other metal that is inert to the chemicals used. A variety ofplastics and ceramics may be used as long as they are inert to thechemical and electrochemical environment. Examples of plastics andceramics are polypropylene, polyethylene, alumina, zirconia. Enclosure702 may also include a fire retardant mesh affixed to the exterior ofthe enclosure for the purpose of preventing fire from reaching theinterior of the enclosure.

In one embodiment, a lid (not shown) may be secured to enclosure 702 toform a hermetically sealed system. The lid may be secured to theenclosure 702 using traditional fabrication techniques. In the case ofmetal components, welding methods, such as laser welding, may be used tosecure a lid with respect to enclosure 702. In the case of plastics,adhesives (glues), or thermal or ultrasonic weld methods may be used, orany combination thereof.

In another embodiment, a first plate and side walls are joined to form aenclosure 702, using traditional fabrication techniques. In the case ofmetal components, welding methods, such as laser welding, may be used toform enclosure 702. In the case of plastics, adhesives (glues), orthermal or ultrasonic weld methods may be used, or any combinationthereof. Once the operative elements are positioned within enclosure702, a second plate (or lid) may be secured thereto to define ahermetically sealed system.

In the exemplary embodiment depicted in FIG. 7, enclosure 702 furtherincludes six (6) distinct compartmentalized regions 705 containing sixdistinct support member(s) 704. The compartmentalized regions 705 (i.e.,compartmentalized regions 705(A)-705(F)) are separated by shared walls706 (i.e., shared walls 706(a)-706(e)). Shared walls 706 may befabricated from the same or a similar material as is used in fabricationof enclosure 702. Further, shared walls 706 may be fabricated as anintegral part of enclosure 702 (e.g., integral with the base or a sidewall of enclosure 702), or may be fabricated as a separate componentthat is attached to enclosure 702 using fabrication techniques asdescribed above. Further, shared wall(s) may define partial walls or maydefine full walls. For partial shared walls 706, enclosure 702 woulddefine a shared atmosphere across and between adjacent compartmentalizedregions; however, for full shared walls 706, i.e., shared walls thatextend from the base to the top/lid of the battery system, eachcompartmentalized region would have an individual/distinct (i.e.,unshared) atmospheric region. In implementations where theelectrochemical units are deployed in a serial connection, full sharedwalls 706 may be advantageously utilized to fully isolate eachcompartmentalized region 705, e.g., to prevent communication of a firstshared atmosphere region with a second shared atmosphere region (andsimilar isolation by the full shared walls between all adjacentcompartmentalized regions).

Since enclosure 702 features a continuous surface (e.g., top plate,bottom plate, side wall) that is in direct communication with eachcompartmentalized region 705, a cooling plate or cooling element may bein contact with and/or attached with respect to a continuous surface(e.g., top plate, bottom plate, side wall) of enclosure 702 tofacilitate cooling of electrochemical units 102 positioned therewith.Inclusion of a cooling plate/cooling element may function to eliminatethe need for other cooling features, e.g., an interspaced coolingcircuit woven between the cells, thereby providing cost-savings ascompared to certain conventional systems. In another embodiment,individual cooling plates/cooling elements may be positioned within eachcompartmentalized region 705 and the features/geometries of theindividual cooling plates/cooling elements may vary fromcompartmentalized region-to-compartmentalized region, e.g., based on thedesign and operation of the electrochemical units positioned with suchcompartmentalized regions 705.

Incorporating individual compartmentalized regions 705 within oneenclosure 702 allows for a more efficient and cost-effective packagingand the ability to house substantially more lithium ion core members ina comparable volume using conventional packaging techniques that involveseparate battery modules. For example, with reference to the exemplaryembodiment of FIG. 7, six distinct compartmentalized regions 705 areschematically depicted. In conventional battery systems, each of thosecompartmentalized regions would take the form of a distinct batterymodule. In the conventional systems, when two modules are placedside-by-side, an outer wall of the first battery module would be inphysical contact with an opposed outer wall of the second batterymodule. In the advantageous battery system depicted in FIG. 7,effectively five walls are eliminated because a single shared wall 706is positioned between adjacent compartmentalized regions 705 (ratherthan side-by-side outer walls). In this way, additional “real estate” isprovided for energy-producing electrochemical units when comparing asimilar overall form factor dimension. Further, the elimination of theindividual enclosures and the use of a shared wall between adjacentcompartmentalized regions reduces cost by eliminating additional and/orredundant materials. The multi-compartmentalized region of exemplaryenclosure 702 is easily scalable and may vary in size to meet desiredsize and power output for a particular customer and/or application. Ofnote, according to the exemplary approach depicted in FIG. 7, the numberof compartmentalized regions is always at least two (i.e., there is atleast one shared wall 706), but is scalable to significantly largersizes, as will be apparent to persons skilled in the art.

As noted above, in the exemplary embodiment of FIG. 7, enclosure 702includes six compartmentalized regions 705A-F and five shared walls 706a-e. Within each compartment 705 is a support member 704, which isconfigured to maximize the quantity of ion core members 102 housedtherein; see FIG. 2 for exemplary ion core member 102 cavityconfigurations. In an illustrious embodiment, support member 704includes 78 ion core members 102 housed in an off-centered/staggeredconfiguration, per compartmentalized region. Accordingly, 468 ion coremembers 102 are housed within the six evenly distributedcompartmentalized regions 705 of enclosure 702.

Further, in implementations where core members 102 are electricallyconnected in parallel, enclosure 702 safely supports a shared atmosphereacross and between compartmentalized regions, at least in part becausethe vapor pressures generated by the “open” jelly rolls are lower thanin systems that place the core members 102 in serial connection. Asnoted above, a shared atmosphere between and among adjacentcompartmentalized regions 705 is provided when the shared wall 706between the adjacent compartmentalized regions extends only a partialdistance from the base plate to the top plate/lid of enclosure 702. Dueto the spacing between the partial shared wall and at least oneboundary/outer wall of enclosure 702, the relevant compartmentalizedregions are not hermetically sealed relative to each other. The sharedatmosphere permits communication of vapors—and a sharing of pressurebuild-up—across and between the individual compartmentalized regions705. In the event of instability and/or a failure of a core member, thegasses expelled from such core member are able to occupy the sharedatmosphere region, which provides significantly more volume toaccommodate such gas/pressure build-up (and shared venting/pressuredisconnect functionality) as compared to conventional modular batterysystems.

A cavity liner may be placed/positioned within each cavity of thesupport member(s) 704, and the lithium ion core members 102 may bepositioned within the noted liners. All cavity liners (e.g., in theexemplary embodiment depicted in FIG. 7, seventy eight (78) cavityliners corresponding to the number of cavities/lithium ion core membersin each compartmentalized region) may be formed as part of a monolithiccavity liner member or they may be individually formed. The cavity lineris generally fabricated from polypropylene, polyethylene, or any otherplastic that is chemically inert to electrolyte. The liner may also bemade of a ceramic or metal material. However, in the case where thesupport member is electrically conductive, the cavity liners aregenerally electrically insulating so as to electrically isolate thelithium ion core members from the support member. The disclosed cavityliners may serve several beneficial functions, e.g., the cavity liners(i) are moisture and electrolyte impermeable, (ii) may contain flameretarding agents, which can quench a fire, and/or (iii) facilitatemaintaining the electrolyte associated with each lithium ion core memberwithin a hermetic seal.

During manufacturing, cavities of the support member can besimultaneously filled with electrolyte and then simultaneously formedand graded for capacity during the continued manufacturing process. Theforming process may include charging the cell to a constant voltage,e.g., 4.2V and then letting the cell rest at this potential for a periodof time, e.g., 12-48 hours. The capacity grading generally takes placeduring a charge/discharge process, where the cell is fully discharged toa lower voltage, such as 2.5V, then charged to a higher voltage,typically in a range of 4.2-4.5V, and subsequently discharged again,upon which the capacity is recorded. Multiple charge/discharge cyclesmay be needed or used to obtain an accurate capacity grading.

The disclosed cavity liner enables a precise and consistent amount ofelectrolyte to be introduced to each core member, due to its snug fitwith the core. One way to accomplish the filling is with through holesin enclosure 702 which can then be filled and sealed after theelectrolyte has been introduced to the cavities. A jelly roll type coremember having about 3 Ah capacity may need about 4-8 g of electrolyte,depending on density and surrounding porous material. Electrolytefilling is generally undertaken so that entire jelly roll is equallywetted throughout the roll with no dry areas allowed.

The size, spacing, shape and number of cavities in support member 704can be adjusted and optimized to achieve desired operatingcharacteristics for the battery while still achieving “packing density”and safety features as described above, such as mitigating failurepropagation between/among core members 102.

Further, in a shared atmosphere enclosure, at least one pressuredisconnect device/feature may be incorporated within and/or on a face ofenclosure 702. The pressure disconnect device/feature may be of the typedisclosed in U.S. non-provisional patent application, assigned Ser. No.15/562,792 to Onnerud et al. The contents of the foregoing applicationis incorporated by reference herein. The pressure threshold, asmentioned below, may be greater than 5 psig, e.g., 5 psig to 40 psig.

In exemplary embodiments, a pressure disconnect device (“PDD”)advantageously electrically isolates electrochemical units 102associated with the lithium ion battery in response to a build-up ofpressure within enclosure 702 that exceeds a predetermined pressurethreshold. The PDD includes a deflectable dome structure and a fuseassembly positioned on an external face of enclosure 702 that isadapted, in response to a pressure build-up within enclosure 702 beyonda threshold pressure level, to electrically isolate lithium ion batterycomponents within enclosure 702. Attached to the fuse assembly is astructural feature that is aligned with the center line of thedeflectable dome.

When the internal pressure reaches the PDD threshold value, thedeflectable dome pops up to contact the structural feature causing ashort circuit between positive and negative terminals, which results infuse failure. After the fuse has failed (i.e., “blown”), the negativeterminal connecting to the external circuit is isolated from jelly rollsin the container, and the negative terminal is kept connecting to thepositive terminal via enclosure 702 and structural feature, resulting incurrent directly flowing from the negative terminal to enclosure 702,i.e., by-passing jelly rolls 102.

In another exemplary embodiment, overcharge electrical disconnectfeature advantageously electrically isolates electrochemical units 102associated with the lithium ion battery in response to a build-up ofpressure within enclosure 702 that exceeds a predetermined pressurethreshold. The overcharge electrical disconnect feature leverages theknown characteristics of enclosure 702, i.e., battery case expansion inresponse to an increase in internal pressure, to disconnectelectrochemical units 102 from enclosure 702. Applicant's concurrentlyfiled provisional patent application entitled “Overcharge ElectricalDisconnect Feature” discloses exemplary embodiments thereof, the contentof which is hereby incorporated by reference.

As mentioned above, enclosure 702 may include a bus bar that is inelectrical contact with electrochemical units 102 and in electricalcontact with a deflectable surface of the enclosure 702, e.g., adeflectable bottom plate. As the internal pressure of enclosure 702increases, the potential for expansion and deformation of enclosure 702will also increase. Top and bottom plate have the largest surface areaand therefore will generally have the greatest potential to expand/bulgeas compared to the side walls. As a force is applied against the bottomplate, due to an increased internal pressure, the resistance welds,attaching the bus bar to the bottom plate, will be under stress and willultimately cause the resistance welds to break/pop, which creates gapbetween the bus bar and the bottom plate. The gap electricallydisconnects the jelly rolls from the bottom plate of enclosure 702.

As mentioned above, within each compartmentalized region 705 (i.e.,regions 705A-705F) is an electrically insulated support member 704 whichmay be fabricated from ceramic, plastic, such as polypropylene,polyethylene, or other materials, such as aluminum foam. Support member704 may be sufficiently deformable/compressible so as to protect thecore members 102 from damage when/if an impact occurs. In addition, itis desired that the thermal conductivity be tailored to the applicationby means of dispersing heat during charge and discharge of the battery,creating a uniform temperature distribution, and by means of divergingheat during a catastrophic failure, such as an internal short causingthermal runaway of one core member. Proper heat dispersing propertieswould limit the chance of cascading runaway between cores. Supportmember 704 may also be absorptive to electrolyte, which may beconstrained in support member 704, should it be expelled during abuse ofcore member 102.

A deformable and kinetic energy absorbing support member 704 isparticularly desirable, as it distributes impact loads over larger areasreducing the amount of local deformation at each core member 102,thereby reducing the likelihood of an electric short circuit. Examplesof kinetic energy absorbing materials are foams, such as aluminum foam,plastic foams, porous ceramic structures, honeycomb structures, or otheropen structures, fiber filled resins, and phenolic materials. An exampleof fiber fillers for plastic and resin materials could be glass fiber orcarbon fibers. Examples of aluminum containing energy absorbers arealuminum foam, having open or closed pores, aluminum honeycombstructures, and engineered material such as the Altucore™ and CrashLite™materials. As the support member collapses during impact, crash or othermechanical abuse, it is important that the cores, as much as possible,are protected from penetration as to avoid internal mechanically inducedshorts. This creates a safer structure. Further discussion with regardsto energy absorbers is disclosed above and with further reference toFIG. 1C.

Support member(s) 704 may be sufficiently deformable/compressible so asto protect the core members 102 from damage when/if an impact occurs. Inaddition, it is desired that the thermal conductivity be tailored to theapplication by means of dispersing heat during charge and discharge ofthe battery, creating a uniform temperature distribution, and by meansof diverging heat during a catastrophic failure, such as an internalshort causing thermal runaway of one core member. Proper heat dispersingproperties would limit the chance of cascading runaway between cores.Support member 704 may also be absorptive to electrolyte, which may beconstrained in support member 704, should it be expelled during abuse ofcore member 102.

A deformable and kinetic energy absorbing support member 704 isparticularly desirable, as it distributes impact loads over larger areasreducing the amount of local deformation at each core member 102,thereby reducing the likelihood of an electric short circuit. Examplesof kinetic energy absorbing materials are foams, such as aluminum foam,plastic foams, porous ceramic structures, honeycomb structures, or otheropen structures, fiber filled resins, and phenolic materials. An exampleof fiber fillers for plastic and resin materials could be glass fiber orcarbon fibers. Examples of aluminum containing energy absorbers arealuminum foam, having open or closed pores, aluminum honeycombstructures, and engineered material such as the Altucore™ and CrashLite™materials. As the support member collapses during impact, crash or othermechanical abuse, it is important that the cores, as much as possible,are protected from penetration as to avoid internal mechanically inducedshorts. This creates a safer structure. Further discussion with regardsto energy absorbers is disclosed above and with further reference toFIG. 1C.

Structure for Controlling Gas/Fluid Flow from Electrochemical Unit(s)

In an exemplary embodiment, enclosure 116, 616, 702 may include astructure for controlling gas/fluid flow from electrochemical unit(s)positioned therewithin. In exemplary embodiments and as shown in FIG. 8,the disclosed structure for controlling gas/fluid flow may take the formof blanket or mat 804 positioned in contact with (or in close proximityto) jelly roll assemblies 102—particularly the open end of jelly rollassemblies 102—housed within support member 120, 620, 702, 802. Blanket804 substantially limits the quantity of hot particulate residue, e.g.,liquid electrolyte and electrolyte gas, from interacting with adjacentjelly rolls 102 if/when released from one or more jelly roll(s). Inexemplary embodiments, blanket 804 includes apertures/features thatfacilitate charging of electrolyte and electrical connection between theelectrochemical units and an associated bus bar.

Blanket 804 generally features flow characteristics that promote axialgas and fluid flow through blanket 804, but substantially reduceslateral (e.g., side-to-side) flow within blanket 804. Therefore,particulates associated with such gas/fluid flow are forced through thebody of blanket 804 and into the shared atmosphere of enclosure 116,616, 702 (or individual compartmentalized region 707). To the extent anapplicable threshold pressure is reached within the shared atmosphere,the particulate-containing gas/fluid is vented from the enclosure.

In an illustrious embodiment, blanket 804 is fabricated from a ceramicmaterial (or similar material) with a pore size/structure that promotesaxial flow therethrough. The ceramic material is typically stable atrelatively high temperatures, e.g., greater than 200° C. In exemplaryembodiments of the present disclosure, the pore size of the disclosedblanket is sized so as to (i) capture larger hot particulates/debris,e.g., larger sized carbonized debris, metal debris, metal oxideparticulates and melted metal particulates, so as to ensure those largerparticulates/debris do not contact adjacent jelly rolls 102, and (ii)facilitate smaller particulates and gas in passing through blanket 804and out the vent (if the vent is activated). Smaller particulates forpurposes of the present disclosure are those particulates that will passfreely through the vent so as to not become trapped/clogged within thevent outlet. In an illustrious embodiment, blanket 804 is installedbeneath bus bar 806; however, blanket 804 may be installed above bus bar806.

Although the disclosed structure for controlling gas/fluid flow fromelectrochemical unit(s) is described/depicted as a blanket 804, it isnoted that the desirable functionality of controlling gas/fluid flow maybe achieved by a plurality of discrete elements that are positioned inproximity to the electrochemical units, e.g., in a one-on-one manner.Thus, individual gas/fluid flow elements may be positioned in proximityto the open end of individual jelly rolls to facilitateaxial/non-lateral flow of gas/fluid that is expelled from the jellyrolls—while capturing larger particulates—as described above withreference to blanket 804. In like manner, the disclosed structure forcontrolling gas/fluid flow may be configured/dimensioned as a structurethat provides flow control functionality with respect to a sub-set ofelectrochemical units positioned within the enclosure, e.g., a row orcolumn of electrochemical units.

Enclosure Embodiments

In a further exemplary embodiment of the present disclosure and withreference to FIG. 9A, enclosure 116, 616, 702 may be configured with anegg box shaped wall 900, such that upon mechanical impact on theenclosure, the MC battery can be short circuited externally of theenclosure. Egg box shaped portion 902 of the wall 900, made out ofaluminum, contacts a plate of non conductive material 904, made ofpolyethylene plastic (prior to impact). A second plate 906, which ismade out of aluminum or other conductive material, is located below theplastic plate 904. The egg box shaped material 902 is connected toeither the negative or the positive pole of the MC battery and the otherconductive plate 906 is connected to the opposite pole. Upon impact,nail penetration, or non-normal pressure on the wall, such as in acrash, the egg box shaped wall 902 compresses so that the plastic plate904 is penetrated and makes contact with conductive plate 906 externalcontact points 908 a-d, FIG. 9B, creating an external electrical shortcircuit in the MC battery.

The individual core members are typically connected by means of aninternal bus bars, as described above. Sometimes the bus bar commonconnector may be a wire or plastic coated wire. It can also be a solidmetal, such as copper, aluminum or nickel. This bus bar connectsmultiple core members in series or parallel and has the capability oftransferring currents in the multi-core member structure to a connector,allowing an external connection to the multi-core array. In the case ofexternal bus bar individual feed through connectors through theenclosure from each jelly roll would be needed.

Whether internal or external bus bars are used, they may be constructedto provide a fuse between the core members. This may be accomplished ina variety of ways, including creating areas where the cross section ofthe bus bar is limited to only carry a certain electrical current or bylimiting the tab size, which connects the core member to the bus bar.The bus bar or tabs may be constructed in one stamped out piece, orother metal forming technique, or by using a second part that connectsthe divisions of the bus bars with a fuse arrangement. For instance, iftwo rectangular cross section areas of copper bus bars are used, whereanode and cathode tabs of 10 core members are connected to each of bythe bus bar, each bus bar having a cross sectional surface area of 10mm², at least one area on the bus bar can be fabricated to have areduced surface area compared to the rest of the bus bar. This providesa position where fusing occurs and current carrying capability islimited. This fuse area may be at one or more points of the bus bar,preferably between each core member, but most effective in the case ofmany cells at the mid-point. If an external short were to occur, thisfuse would limit the heating of the core members and potentially avoidthermal runaway. Also in the case of internal shorts in a core member,either due to manufacturing defects or due to external penetrationduring an abuse event, such as a nail, that penetrates into the coremembers causing an internal short to the cell, this fuse arrangement maylimit the amount of current that is transferred to the internal short byshutting of the malfunctioning core to the other parallel cores.

Empty space inside the enclosure can be filled with shock absorbingmaterials, such as foam or other structure that allows less impact tothe core members, thereby further reducing the risk of internal shorts.This ruggedization may also provide means of shifting the self-vibrationfrequency of the internal content to the enclosure, providing increasedtolerance to shock and vibration and mechanical life. The fillermaterial should preferably contain fire retardant materials that wouldallow extinguishing of any fire that could arise during thermal runawayof the cell or melt during the same thermal runaway, thereby taking upexcess heat and limit the heating of a cell. This provides for increasedsafety in the case of catastrophic event.

Examples of fire retardants can be found in the open engineeringliterature and handbooks, such as Polyurethanes Handbook published byHanser Gardner Publications or as described in U.S. Pat. No. 5,198,473.Besides polyurethane foam also epoxy foams or glass fiber wool andsimilar non-chemically or electrochemically active materials, may beused as filler materials in empty spaces inside the enclosure. Inparticular, hollow or dense spheres or irregularly shaped particulatesmade of plastic, metal or ceramic may be used as low cost fillers, inthe case of hollow spheres, these would provide additional means forenergy absorption during a crash scenario of the multi core cell. In aspecial case, the support member is aluminum foam. In another specialcase, the support member is dense aluminum foam between 10-25% ofaluminum density. In yet another special case, the pores in the aluminumfoam has an average diameter that is less than 1 mm.

Enclosure 116, 616, 702 may further be configured with a clamshellconfiguration, wherein symmetrically identical side wall components areattached together along a pair of seams to define enclosure 116, 616,702. In one exemplary embodiment, the side wall components attach alonga vertical seam centrally located on enclosure 116, 616, 702. In anotherexemplary embodiment, the clamshell configuration attaches along ahorizontal seam centrally located on enclosure 116, 616, 702. In yetanother exemplary embodiment, the clamshell configuration attaches alongan angled seam that symmetrically divides enclosure 116, 616, 702. Inyet another exemplary embodiment, the exterior of both side wallcomponents are identical, but the interior base of one or both of theside wall components includes a partial or full separating wall, e.g.,shared wall, for formation of individual compartmentalized regionswithin enclosure 702.

With reference to FIG. 10, exemplary side wall component 1000 includesat least one side wall 1002 and base 1004 in a substantially “L” shapedconfiguration. Side wall component 1000 may further include cutout(s)for a PDD device 1006 and/or a vent/flame arrestor 1008, configured intobase 1004. However, to ensure each side wall component 1000 issymmetrically identical during the initial manufacturing process,cutouts 1006, 1008 (and others) may be incorporated after the initialfabrication of side wall component 1000. In yet another embodiment, oneor more cutouts 1006, 1008 may be fabricated into sidewall 1002.

To assemble side wall component 1000, one side wall component 1000 isrotated so as to ensure that each base 1004 interfaces with an edge ofside wall 1002. A correctly fabricated clamshell configuration (notshown) using two side wall components 1000 will create a substantiallyrectangular configuration. However, additional configurations will beapparent to persons skilled in the art. The above-mentioned clamshellconfigurations may provide a cost-savings by substantially reducingmanufacturing/assembly operations. For example, the disclosed clamshellcomponents may be advantageously joined around one or more pre-assembledsupport members that contain electrochemical units, as disclosed herein.Thus, assembly is greatly facilitated by allowing the pre-assembly ofthe electrochemical units within support member(s) before associatingthe noted sub-assembly with an outer enclosure. Once the clamshellelements are positioned around the support member(s) and the seams arewelded, an hermetic enclosure may be established in the same manner asnon-clam shell assembly protocols, e.g., by combining the clamshellcomponents with a base and lid to define a fully enclosed andhermetically sealed structure.

In an illustrious embodiment, the clamshell components are fabricatedusing plastic or ceramic materials, but may also be made of metal. If ametal is used, exposed steel is not preferred, and any steel containerwould need to be coated with an inert metal such as nickel. Preferredmetals are aluminum, nickel or other inert metal to the chemicals used.A variety of plastics and ceramics may be used as long as they are inertto the chemical and electrochemical environment. Examples of plasticsand ceramics are polypropylene, polyethylene, alumina, zirconia. In thecase of metal components, welding methods, such as laser welding, may beused to seal the clamshell components. In the case of plastics,adhesives (glues), or thermal or ultrasonic weld methods may be used, orany combination thereof. Once assembled, this provides for ahermetically sealed modular enclosure 116, 616, 702. The clamshellcomponents may also include a fire retardant mesh affixed to theexterior of the clamshell components for the purpose of preventing firefrom reaching the interior of the enclosure/compartments.

Anode

The anode of these core members are those commonly found in Li-ion or Lipolymer batteries and described in the literature, such as graphite,doped carbon, hard carbon, amorphous carbon, Silicon (such as siliconnano particles or Si pillars or dispersed silicon with carbon), tin, tinalloys, Cu₆Sn₅, Li, deposited Li onto metal foil substrates, Si with Li,mixed in Li metal powder in graphite, lithium titanate, and any mixturesthereof. Anode suppliers include, for example, Morgan Carbon, HitachiChemical, Nippon Carbon, BTR Energy, JFE Chemical, Shanshan, TaiwanSteel, Osaka Gas, Conoco, FMC Lithium, Mitsubishi Chemical. Thedisclosure is not limited to any particular anode compound.

Cathode

The cathode used for the jelly rolls are those that are standard for theindustry and also some new high voltage mixtures, which are described inmore detail below. These new cathodes can be used in MC structures or insingle cell batteries wherein the anode/cathode structure is containedin a sealed metal canister or a sealed polymer bag. Due to the richnessof cathode materials available to the industry, the classes of materialsas to each materials group herein are referred to as “Compounds”; eachcompound can have a range of compositions and are grouped due tosimilarity in crystal structure, chemical composition, voltage rangesuitability, or materials composition and gradient changes. Examples ofsuitable individual materials are Li_(x)CoO₂ (referred to as CompoundA), Li_(x)M_(z)Co_(w)O₂ (Compound B, where M is selected from Mg, Ti,and Al and partly substituting Co or Li in the crystal lattice and addedin the range Z=0-5%, typically W is close to 1, suitable for chargeabove 4.2V), Li_(x)Ni_(a)Mn_(b)Co_(c)O₂ (in particular the combinationsof about a=1/3, b=1/3, c=1/3 (Compound C) and a=0.5, b=0.3, c=0.2(Compound D), and Mg substituted compounds thereof (both grouped underCompound E)).

Another example is Li_(x)Ni_(d)Co_(e)Al_(f)O₂ (Compound F) and its Mgsubstituted derivative Li_(x)Mg_(y)Ni_(d)Co_(e)Al_(f)O₂ (Compound G),where in a special case d=0.8, e=0.15, f=0.05, but d, e, and f can varywith several percent, y ranges between 0 and 0.05. Yet another exampleof individual cathode materials are Li_(x)FePO₄ (Compound H),Li_(x)CoPO₄ (Compound I), Li_(x)MnPO₄ (Compound J), and Li_(x)Mn₂O₄(Compound K). In all of these compounds, an excess of lithium istypically found (x>1), but X can vary from about 0.9 to 1.1. A class ofmaterials that is particularly suited for high voltages, possessing highcapacity when charged above 4.2V, are the so-called layered-layeredmaterials described for instance by Thackeray et al. in U.S. patent U.S.Pat. No. 7,358,009 and commercially available from BASF and TODA(Compound L).

The compound initially described by Thackeray can be made stable atvoltages above 4.2V. Some of these cathodes are stable at high voltages,above 4.2V (the standard highest voltage using graphite as anode) andthose materials can be preferably mixed. Although one of the abovematerials can be used in the disclosure, it is preferred to mix two ormore of the materials compounds selected from B, C, D, E, F, G I, J, andL. In particular two or more component mixture of the Compounds B, D, F,G, and L is preferred. For very high energy density configurations amixture of (B and L) or (B and G) or (G and L) are most beneficial andwhen these are made as thin electrodes also high power can be achieved.The thin (power) and thick (energy) electrodes can enter into coremembers for tailoring of energy to power ratio, while having samesuitable voltage range and chemistry.

A particular new cathode, the so-called, core shell gradient (CSG)material (referred to as Compound M), has a different composition at itscore compared to its shell. For instance Ecopro(website www.ecopro.co.kror (http://ecopro.co.kr/xe/?mid=emenu31, as of date 2010-10-01) orPatent Application and registration PCT/KR2007/001729(PCT) (2007), whichdescribes such a Compound M material in their product literature as “CSGmaterial” (Core Shell Gradient) as xLi[Ni_(0.8)Co_(0.1)Mn_(0.1)]O₂(1-x)Li[Ni_(0.46)Co_(0.23)Mn_(0.31)]O₂ andanother M-type compound is also described by Y-K Sun inElectrochimicaActa Vol. 55 Issue 28 p. 8621-8627, and third descriptionof M-type compound can be found by in Nature Materials 8 (2009) p.320-324 (article by Y K Sun et al), which describes a CSG material ofsimilar composition but formula Bulk=Li(Ni_(0.8)Co_(0.1)Mn_(0.1)O₂,gradient concentration=Li(Ni_(0.8-x)Co_(0.1+y)Mn_(0.1+z), where0≤x≤0.34, 0'y≤0.13, and 0≤z≤0.21; and surfacelayer=Li(Ni_(0.46)Co_(0.23)Mn_(0.31))O₂. A forth description can befound in patent WO2012/011785A2 (the “785A2” patent), describing themanufacturing of variants of Compound M described asLi_(x1)[Ni_(1-y1-z1-w1)Co_(y1)Mn_(z1)M_(w1)]O₂ (where, in the aboveformula, 0.9≤x1≤1.3, 0.1≤y1≤0.3, 0.0≤z1≤0.3, 0≤w1≤0.1, and M is at leastone metal selected from Mg, Zn, Ca, Sr, Cu, Zr, P, Fe, Al, Ga, In, Cr,Ge, and Sn); and an exterior portion including the compound ofLi_(x2)[Ni_(1-y2-z2-w2)Co_(y2)Mn_(z2)M_(W2)]O₂ (where, in the exteriorformula, 0.9≤x2≤1+z2, 0≤y2≤0.33, 0≤z2≤0.5, 0≤w2≤0.1 and M is at leastone metal selected from Mg, Zn, Ca, Sr, Cu, Zr, P, Fe, Al, Ga, In, Cr,Ge, and Sn). All four ranges of variants of compound M are incorporatedherein as reference for Compound M to be used in various aspects of thedisclosure.

It is preferred that the M compound may further have Li content thatcould be at about 1, but vary within a few percent and that the Li orNi/Mn/Co compounds can be substituted with Mg, Al and first rowtransition metals, by optimization, and that it is preferred to blendone or more of these M compounds as described above with Compounds B, C,D, E, F, G, L for use in Li-ion batteries. It is likely that the coreCompound M material can contain up to 90% nickel and as low as 5% Cobaltand up to 40% Mn, and the gradient would then go from one of theseboundary compositions to as low as 10% Ni, 90% Cobalt, and 50% Mn.

In general, high power can be achieved by using thin electrodes of thecompounds or blends described within this disclosure for anode andcathodes. A thick electrode is typically considered to be above 60 μm ofthickness up to about 200 μm, when measuring the electrode coating layerthickness from the aluminum foil, while thinner electrodes (i.e. lessthan 60 μm) are better for high power Li-ion battery configurations.Typically for high power, more carbon black additive is used in theelectrode formulations to make it more electrically conductive. Cathodecompounds can be bought from several materials suppliers, such asUmicore, BASF, TODA Kogyo, Ecopro, Nichia, MGL, Shanshan, and MitsubishiChemical. Compound M, is available from Ecopro and described in theirproduct literature as CSG material (such asxLi[Ni_(0.8)Co_(0.1)Mn_(0.1)]O₂(1-x)Li[Ni_(0.46)Co_(0.23)Mn_(0.31)]O₂]and another M-type compound also as described by Y-K Sun inElectrochimicaActa Vol. 55 Issue 28 p. 8621-8627, all of which canpreferably be blended with compounds as described above.

The compounds A-M blended as two or more compounds into high voltagecathodes can preferably be coated with a surface modifier. When asurface modifier is used, it is preferred, although not necessary, thateach compound is coated with the same surface modifier. The surfacemodifier helps increase first cycle efficiency of the cathode mixtureand rate capability. Also, useful life is improved with applying thesurface modifying material. Examples of surface modifiers are Al₂O₃,Nb₂O₅, ZrO₂, ZnO, MgO, TiO₂, metal fluorides such as AlF₃, metalphosphates AlPO₄ and CoPO₄. Such surface modifying compounds have beendescribed in the literature earlier[J. Liu et al, J. of MaterialsChemistry 20 (2010) 3961-3967; S T Myung et al., Chemistry of Materials17 (2005) 3695-3704; S. T. Myung et al., J. of Physical Chemistry C 11 1(2007) 4061-4067; ST Myung et al., J. of Physical Chemistry C 1 154(2010) 4710-4718; BC Park et al, J. of Power Sources 178 (2008) 826-831;J. Cho et al., J of Electrochemical Society 151 (2004) A1707-A1711], butnever reported in conjunction with blended cathodes at voltages above4.2V. In particular it is beneficial to blend surface modified compoundsB, C, D, E, F, G, L and M for operation above 4.2V.

The cathode material is mixed with a binder and carbon black, such asketjen black, or other conductive additives. NMP is typically used todissolve the binder and PVDF is a preferred binder for Li-ion, while Lipolymer type can have other binders. The cathode slurry is mixed tostable viscosity and is well known in the art. Compounds A-M and theirblends described above are herein sometimes referred collectively as“cathode active materials”. Similarly anode compounds are referred to asanode active materials.

A cathode electrode can be fabricated by mixing for instance a cathodecompound, such as the blends or individual compounds of Compound A-Mabove, at about 94% cathode active materials and about 2% carbon blackand 3% PVDF binder. Carbon black can be Ketjen black, Super P, acetyleneblack, and other conductive additives available from multiple suppliersincluding AkzoNobel, Timcal, and Cabot. A slurry is created by mixingthese components with NMP solvent and the slurry is then coated ontoboth sides of an Aluminum foil of about 20 micrometer thickness anddried at about 100-130° C. at desired thickness and area weight. Thiselectrode is then calendared, by rolls, to desired thickness anddensity.

The anode is prepared similarly, but about 94-96% anode active material,in case of graphite, is typically used, while PVDF binder is at 4%.Sometimes SBR binder is used for cathode mixed with CMC and for thattype of binder higher relative amounts of anode active materials atabout 98% can typically be used. For anode, carbon black can sometimesbe used to increase rate capability. Anode is coated on copper foil ofabout 10 micrometer.

Those skilled in the art would easily be able to mix compositions asdescribed above for functional electrodes.

To limit electrode expansion during charge and discharge fiber materialsof PE, PP, and carbon can optionally be added to the electrodeformulation. Other expansion techniques use inert ceramic particulatessuch as SiO₂, TiO₂, ZrO₂ or Al₂O₃ in the electrode formulation.Generally the density of cathodes is between 3 and 4 g/cm³, preferablybetween 3.6 and 3.8 g/cm³ and graphite anodes between 1.4 and 1.9 g/cm³,preferably 1.6-1.8 g/cm³, which is achieved by the pressing.

Separator

The separator needs to be an electrically insulating film that isinserted between anode and cathode electrodes and should have highpermeability for Li ions as well as high strength in tensile andtransverse direction and high penetration strength. The pore size istypically between 0.01 and 1 micrometer and thickness is between 5micrometer and 50 micrometer. Sheets of non-woven polyolefins, such aspolyethylene (PE), polypropylene (PP) or PP/PE/PP structures aretypically used. A ceramic, typically consisting of Al₂O₃, may be appliedonto the film to improve shrinking upon heating and improve protectionagainst internal shorts. Also the cathode or the anode can be coatedsimilarly with a ceramic. Separators can be procured from multiplesuppliers in the industry including Celgard, SK, Ube, Asahi Kasei,Tonen/Exxon, and WScope.

Electrolyte

The electrolyte is typically found in the industry containing solventsand salts. Solvents are typically selected between DEC (diethylcarbonate), EC (ethylene carbonate), EMC (ethyl methyl carbonate), PC(propylene carbonate), DMC (dimethyl carbonate), 1,3dioxolane, EA (ethylacetate), tetrahydrofuran (THF). Salts are selected between LiPF₆,LiClO₄, LiAsF₆, LiBF₄, sulfur or imide containing compounds used inelectrolyte includes LiCFSO₃, LiN(CF₃SO₂)₂, LiN(CF₃CF₂SO₂)₂, or a plainsulfonation by bubbling SO₂ through a premixed electrolyte such asEC/EMC/DMC (1:1:1 ratio) and 1M LiPF₆. Other salts are LiBOB (LithiumBis-oxalateborate), TEATFB (tetraethylammoniumtetrafluoroborate),TEMABF₄ (triethylmethylammoniumtetrafluoroborate). Additive foreffective SEI formation, gas generation, flame retardant properties, orredox shuttling capability can also be used, including BP (biphenyl),FEC, pyridine, triethylphosphite, triethanolamine, ethylenediamine,hexaphosphorictriamide, sulfur, PS (propylenesulfite), ES(ethylenesulfite), TPP (triphenylphosphate), ammonium salts, halogencontaining solvents, such as carbon tetrachloride or ethylenetrifluoride and additionally CO2 gas to improve high temperature storagecharacteristics. For solid/gel or polymer electrolytes PVDF, PVDF-HFP,EMITFSI, LiTFSI, PEO, PAN, PMMA, PVC, any blends of these polymers, canbe used along with other electrolyte components to provide a gelelectrolyte. Electrolyte suppliers include Cheil, Ube, MitsubishiChemical, BASF, Tomiyama, Guotsa-Huasong, and Novolyte.

There are electrolytes that work for both supercapacitors (those havingelectrochemical doublelayers) and standard Li-ion batteries. For thoseelectrolytes one or more supercapacitor cores can be mixed with one ormore regular Li-ion core member in an enclosure, so that thesupercapacitor component works as a power agent and the Li-ion coremember as an energy harvesting agent.

EXAMPLE

In this example a set of 5 jelly roll type core members of cylindricalshape that are connected in parallel to two common bus bars (positiveand negative), like the MC battery configuration shown in FIG. 1, butwith only half as many core members. The negative connector is connectedto the tabs extending from the jelly roll's anode foil (copper), has acoated graphite electrode, and the positive connector to the jellyroll's cathode foil (aluminum) has a blended oxide electrode structureof Compound M and Compound F. The anode tab made out of nickel and thecathode tab made of aluminum is welded to the bus bar using spot weldingor laser welding techniques. The enclosure and support member are madeof plastic material (polyethylene). For this example, cylindricalcavities with an 18 mm diameter and the jelly roll core members with aslightly smaller diameter (17.9 mm) were used. The enclosure and lid aremade of plastic material that is ultrasonically welded together andthereby creating a hermetic seal.

One skilled in the art can select and vary the property of the coremembers, as described above, achieve high energy or high power cores.The table shown below outlines three examples, with varying corecompositions of the 5 core member example described above and thedifferent properties of the MC battery that can be achieved.

CORE EXAMPLE 1 EXAMPLE 2 EXAMPLE 3 1 3 Ah, energy core 1.5 Ah, powercore 2.5 Ah, power core M cathode D cathode (0.8 F/0.2 D) cathode mix 23 Ah, energy core 3.0 Ah, power core 3.0 Ah, power core M M cathode Dcathode cathode 3 3 Ah, energy core 3.0 Ah, power core 3.0 Ah, powercore M M cathode D cathode cathode 4 3 Ah, energy core 3.0 Ah, powercore 3.0 Ah, power core M M cathode D cathode cathode 5 3 Ah, energycore 1.5 Ah, power core 3.0 Ah, power core M M cathode D cathode cathodeSUMMARY IDENTICAL MIXED POWER MIXED POWER AND PROPERTIES ON AND ENERGYENERGY CORES, ALL CORES CORES, MIXED MIXED CAPACITY, CAPACITY, SAMEMIXED VOLTAGE VOLTAGE

The disclosure may be embodied in other specific forms without departingfrom the spirit or essential characteristics thereof. The presentembodiments are therefore to be considered in respects as illustrativeand not restrictive.

The invention claimed is:
 1. A lithium ion battery, comprising: at leasttwo support members, each of the at least two support members includinga plurality of cavities defined by cavity surfaces, wherein each of theplurality of cavities is configured to receive a lithium ion core memberthrough a cavity opening; a plurality of lithium ion core members, eachof the plurality of lithium ion core members (i) including an anode, acathode, a separator positioned between the anode and the cathode, andelectrolyte, and (ii) positioned in one of the plurality of cavities ofthe support member, and a hermetically sealed enclosure that (i) definesor includes a shared wall positioned between two of the at least twosupport members to define two compartmentalized regions, and (ii)defines a first shared atmosphere region within a first of the twocompartmentalized regions and a second shared atmosphere region with asecond of the two compartmentalized regions; wherein each of the lithiumion core members is surrounded by a cavity surface of one of theplurality of cavities along its length such that electrolyte isprevented from escaping the cavity within which it is contained; andwherein the anode, cathode and electrolyte of each ion core membercommunicates with the first shared atmosphere region or the secondshared atmosphere region through a cavity opening when positioned in acavity of the at least two support members.
 2. The lithium ion batteryof claim 1, wherein the first shared atmosphere region is incommunication with the second shared atmosphere region despite theshared wall.
 3. The lithium ion battery of claim 1, wherein the sharedwall prevents communication between the first shared atmosphere regionand the second shared atmosphere region.
 4. The lithium ion battery ofclaim 1, wherein the enclosure includes at least one pressure disconnectfeature.
 5. The lithium ion battery of claim 1, wherein eachcompartmentalized region includes at least one pressure disconnectfeature.
 6. The lithium ion battery of claim 1, further comprising atleast one structure for controlling gas or fluid flow from one or moreof the lithium ion core members.
 7. The lithium ion battery of claim 6,wherein the at least one structure is a blanket in contact with or inclose proximity to one or more of the lithium ion core members.
 8. Thelithium ion battery of claim 6, wherein the at least one structure isfabricated from a ceramic material that is configured and dimensioned topromote axial flow through the structure and to substantially preventlateral flow therethrough.
 9. The lithium ion battery of claim 1,wherein the shared wall is a partial wall that extends only a portion ofa distance between a base and top of the enclosure, or a full wall thatextends from the base to the top of the enclosure.
 10. The lithium ionbattery of claim 1, wherein the at least two support members include akinetic energy absorbing material.
 11. The lithium ion battery of claim1, further comprising a cavity liner positioned in each cavity, whereineach of the cavity liners is formed of a plastic or aluminum materialand receives one of the lithium ion core members.
 12. The lithium ionbattery of claim 1, further including an electrical connector withinsaid hermetically sealed enclosure electrically connecting said ion coremembers to an electrical terminal external to the hermetically sealedenclosure.
 13. The lithium ion battery of claim 1, wherein at least oneof the at least two support members is in the form of a honeycombstructure.
 14. The lithium ion battery of claim 1, wherein thehermetically sealed enclosure includes a wall having a compressibleelement which when compressed due to a force impacting the wall createsan electrical short circuit of the lithium ion battery.
 15. The lithiumion battery of claim 1, wherein the hermetically sealed enclosureincludes a fire retardant member.
 16. The lithium ion battery of claim15, wherein the fire retardant member comprises a fire retardant meshmaterial affixed to the exterior of the hermetically sealed enclosure.17. The lithium ion battery of claim 15, wherein the fire retardantmember is selected from the group consisting of a polyurethane foam, anepoxy foam, and glass fiber wool.
 18. The lithium ion battery of claim1, further including a protective sleeve surrounding each of the ioncore members.
 19. The lithium ion battery of claim 1, wherein theelectrolyte comprises at least one of a flame retardant, a gasgenerating agent, and a redox shuttle.
 20. The lithium ion battery ofclaim 1, wherein at least two of the lithium ion core members areconnected in parallel.
 21. The lithium ion battery of claim 1, whereinat least two of the lithium ion core members are connected in series.22. The lithium ion battery of claim 1, wherein a first set of lithiumion core members are connected in parallel, a second set of lithium ioncore members are connected in parallel, and the first set of lithium ioncore members and the second set of lithium ion core members areconnected in series.
 23. The lithium ion battery of claim 1, whereinelectrical connection of the lithium ion core members is selected fromthe group consisting of: (i) parallel connection of the lithium ion coremembers, (ii) series connection of the lithium ion core members, and(iii) parallel connection of a first set of lithium ion core members,parallel connection of a second set of lithium ion core members, andseries connection of the first set of lithium ion core members and thesecond set of lithium ion core members.
 24. The lithium ion battery ofclaim 1, wherein the hermetically sealed enclosure defines or includes aplurality of shared walls, and wherein the hermetically sealed enclosuredefines compartmentalized regions on either side of each of theplurality of shared walls.